Help with combos

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Help with combos

by Jinglander » Tue Sep 28, 2010 8:58 am
Renee, has a bag of 6 candies, 4 are sweet 2 are sour. if Jack picks two candies simultaneously how many different combinations can he make

At first I thought total combinations its just 6!/2!4! from the combination formula. But when I enumerate them I only get XX,XY,YY. This is because the sours and the sweet are indistinct. Can someone help the the formula that would produce the 3 as the number of outcomes using some combinations trick
Source: — Problem Solving |

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by diebeatsthegmat » Tue Sep 28, 2010 9:27 am
Jinglander wrote:Renee, has a bag of 6 candies, 4 are sweet 2 are sour. if Jack picks two candies simultaneously how many different combinations can he make

At first I thought total combinations its just 6!/2!4! from the combination formula. But when I enumerate them I only get XX,XY,YY. This is because the sours and the sweet are indistinct. Can someone help the the formula that would produce the 3 as the number of outcomes using some combinations trick
i just posted the solution, take a look,,, read manhattan gmat for maths section. it helps

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by Jinglander » Tue Sep 28, 2010 10:12 am
Where did you post the solution. I did read mgmat and I know how to solve with prob just not combos

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by diebeatsthegmat » Tue Sep 28, 2010 4:23 pm
Jinglander wrote:Where did you post the solution. I did read mgmat and I know how to solve with prob just not combos
isnt it right that you posted the question in this link?

https://www.beatthegmat.com/solve-with-c ... tml#302936